Effect of 16, 16-dimethyl PGE2 on resting and histamine-stimulated gastric mucosal blood flow

Abstract

Using [¹⁴C]aminopyrine clearance as a measure of mucosal blood flow, 16, 16-dimethyl PGE₂ was administered orally as a single bolus and its effects on resting and histamine-stimulated gastric mucosal blood flow assessed in conscious dogs with vagally denervated gastric pouches. No effect on resting mucosal flow was observed with any of the doses (ie, 2, 10, and 50 μg/kg) of prostaglandin given. In histamine-stimulated experiments, intravenous infusion of histamine dihydrochloride (1 mg/hr) elicited a significant (P2 on gastric secretion and blood flow was mediated through direct effects on gastric parietal cells rather than any primary alteration in the gastric microcirculation. We conclude that 16,16-dimethyl PGE₂ given orally has no effect on the resting gastric mucosal circulation and that any reduction in mucosal flow during histamine stimulation is secondary to its inhibitory effects on gastric acid secretion.